Vertebral facet joint fusion implant and method for fusion

ABSTRACT

In some embodiments a method comprises disposing an implant into contact with a first bone portion and into contact with a second bone portion, the implant having (1) a first interface configured to receive a restraining member, and (2) a second interface. The method further comprises inserting a portion of the fastener member into the first interface. The method further comprises securing the fastener member such that the first bone portion and the second bone portion are fixed to each other, at least in part by a substance after the securing, at least a portion of the substance disposed through the second interface.

RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No.13/403,698, filed Feb. 23, 2012, which is a continuation-in-part of, andclaims priority to, U.S. Nonprovisional application Ser. No. 13/033,791filed Feb. 24, 2011, now U.S. Pat. No. 8,740,949, and entitled “METHODSAND APPARATUS FOR STABILIZING BONE,” the contents of which are hereinincorporated by reference in its entirety.

BACKGROUND

Some embodiments described herein relate generally to methods andimplants for fusing bone, for example, fusing vertebrae by securing thearticular processes of the vertebrae.

Traumatic, inflammatory, and degenerative disorders of the spine canlead to severe pain and loss of mobility. One source of back and spinepain is related to degeneration of the facets of the spine or facetarthritis. Bony contact or grinding of degenerated facet joint surfacescan play a role in some pain syndromes. While many technologicaladvances have focused on the intervertebral disc and artificialreplacement or repair of the intervertebral disc, little advancement infacet repair has been made. Facet joint and disc degeneration frequentlyoccur together. Thus, a need exists to address the clinical concernsraised by degenerative facet joints.

The current standard of care to address the degenerative problems withthe facet joints is to fuse the two adjacent vertebrae. By performingthis surgical procedure, the relative motion between the two adjacentvertebrae is stopped, thus stopping motion of the facets and anypotential pain generated as a result thereof. Procedures to fuse twoadjacent vertebrae often involve fixation and/or stabilization of thetwo adjacent vertebrae until the two adjacent vertebrae fuse.

Injuries and/or surgical procedure on and/or effecting other bones canalso result in the desire to fixate and/or stabilize a bone until thebone, or bone portions, can fuse, for example, to stabilize a sternumafter heart surgery, to stabilize a rib after a break, etc. Currentprocedures to fixate and/or stabilize adjacent vertebrae and/or otherbones can be slow and/or complex.

Accordingly, a need exists for an apparatus and a procedure to quicklyand/or easily stabilize and/or fixate a bone.

SUMMARY

In some embodiments a method comprises disposing an implant into contactwith a first bone portion and into contact with a second bone portion,the implant having (1) a first interface configured to receive arestraining member, and (2) a second interface. The method furthercomprises inserting a portion of the fastener member into the firstinterface. The method further comprises securing the fastener membersuch that the first bone portion and the second bone portion are fixedto each other, at least in part by a substance after the securing, atleast a portion of the substance disposed through the second interface.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a lateral elevational view of a portion of the vertebralcolumn.

FIG. 2A is a schematic superior view of an isolated thoracic vertebra.

FIG. 2B are schematic side view of an isolated thoracic vertebra.

FIG. 3A is a schematic posterior elevational view of a portion of thevertebral column.

FIG. 3B is a posterior-oblique elevational view of a portion of thevertebral column.

FIG. 4A is a schematic side view of a facet joint in the cervicalvertebrae.

FIG. 4B is a schematic superior view of a facet joint in the cervicalvertebrae.

FIG. 5A is a schematic side view of a facet joint in the thoracicvertebrae.

FIG. 5B is a schematic superior view of a facet joint in the thoracicvertebrae.

FIG. 6A is a schematic side view of a facet joint in the lumbarvertebrae.

FIG. 6B is a schematic superior view of a facet joint in the lumbarvertebrae.

FIG. 7 is a block diagram of an implant according to an embodiment.

FIGS. 8A and 8B are schematic views of one embodiment of a facet jointimplant comprising a circular disc.

FIG. 8C is a schematic view of the implant from FIG. 7A implanted in afacet joint.

FIGS. 9A and 9B are schematic views of one embodiment of a facet jointimplant comprising an octagonal disc.

FIGS. 10A and 10B are schematic views of one embodiment of a facet jointimplant comprising a biconcave disc.

FIGS. 11A and 11B are schematic views of one embodiment of a facet jointimplant comprising a single-face variable thickness disc.

FIGS. 12A and 12B are schematic views of one embodiment of a facet jointimplant comprising a curved disc.

FIG. 13 is a schematic view of the implant from FIG. 12A implanted in afacet joint.

FIGS. 14A and 14B are schematic views of one embodiment of a facet jointimplant comprising a disc with a roughened surface on one face.

FIGS. 15A and 15B are schematic views of one embodiment of a facet jointimplant comprising a disc with a porous surface on one face.

FIGS. 16A and 16B are schematic views of one embodiment of a facet jointimplant comprising a bent disc with a roughened surface on the greaterface.

FIG. 17 is a schematic view of the implant from FIG. 16A implanted in afacet joint.

FIGS. 18A and 18B are schematic views of one embodiment of a facet jointimplant comprising two discs, each with a roughened surface on one face.

FIG. 19 is a schematic view of the implant from FIG. 18A implanted in afacet joint.

FIG. 20 is a schematic view of a fastener member comprising a braidedcable.

FIGS. 21A and 21B are schematic views of one embodiment of a facet jointimplant with a fastener interface comprising a centrally located hole.

FIGS. 22A and 22B are schematic views of one embodiment of a facet jointimplant with a fastener interface comprising an eccentrically locatedhole.

FIGS. 23A and 23B are schematic views of one embodiment of a facet jointimplant with a fastener interface comprising an edge contiguous hole.

FIGS. 24A and 24B are schematic views of one embodiment of a facet jointimplant comprising two discs, each with an eccentrically located hole.

FIGS. 25A and 25B are schematic views of one embodiment of a facet jointimplant comprising a curved disc with a fastener interface.

FIG. 26 depicts one embodiment where the cable is engaged to thearticular processes using knots in the cable.

FIGS. 27A and 27B depict another embodiment of the fastener membercomprising a braided cable with threaded ends adapted to accept threadednuts.

FIG. 28 depicts one embodiment where a cable is engaged to the articularprocesses using nuts threaded onto the cable.

FIG. 29 depicts a preferred embodiment comprising a curved implant,cable and two set-screw fastener rings.

FIGS. 30A and 30B are elevational and cross-sectional views of oneembodiment of the set-screw fastener rings, respectively.

FIGS. 31 through 33 are elevational views of various embodiments of thescrew in the set-screw fastener rings.

FIGS. 34A to 34B are one embodiment comprising friction fit fastenerrings. FIGS. 34A and 34B depict the fastener rings in their reducedstate.

FIGS. 35A and 35B depict the fastener rings of FIGS. 34A to 34B in theirexpanded state.

FIGS. 36A to 36C illustrate embodiments comprising a implant with aclose ended threaded fastener interface and a threaded fastener member.FIGS. 36B and 36C depict a threaded fastener member with a pivotablewasher.

FIG. 37A is a cross sectional view of the implant in FIG. 36A implantedin a facet joint; FIG. 37B is a cross sectional view of the implant inFIG. 36B implanted in a facet joint.

FIG. 38 is a cross sectional view of a two-part implant comprising flatdiscs implanted into a facet joint.

FIG. 39 is a cross sectional view of a two-part implant comprisingcurved discs implanted into a facet joint.

FIGS. 40A and 40B are schematic views of one embodiment of a facet jointimplant with an integral fastener member comprising a centrally locatedbarbed spike.

FIGS. 41A and 41B are schematic views of one embodiment of a facet jointimplant with an integral fastener member comprising an eccentricallylocated barbed spike.

FIG. 42 depicts the implant of FIG. 41A implanted into a facet joint.

FIG. 43 illustrates a two-part implant implanted into a facet joint.

FIG. 44 shows one embodiment comprising a implant with multipleanchoring projections.

FIG. 45 shows the implant of FIG. 44 implanted into a facet joint

FIGS. 46A and 46B depict one embodiment comprising a implant with arigid soft tissue side anchor.

FIGS. 47A and 47B depict one embodiment comprising a implant with anembedded flexible soft tissue side anchor.

FIG. 48A is a perspective view of an implant according to an embodiment.

FIG. 48B is a side view of the implant of FIG. 48A

FIG. 48C is a cross-sectional side view of the implant of FIG. 48A.

FIGS. 49-51 are posterior perspective views of a portion of thevertebral column depicting a method of stabilizing a vertebra using animplant and fastener member according to an embodiment.

FIG. 52 is a flow chart illustrating a method of using the implant andfastener member depicted FIGS. 49-51.

FIG. 53 is a perspective view of a flexible fastening band according toan embodiment.

FIG. 54 is a perspective view of a portion of the flexible fasteningband depicted in FIG. 53.

FIG. 55 is a side view of a flexible fastening band according to anembodiment.

FIG. 56 is a top view the flexible fastening band depicted in FIG. 55.

FIG. 57 is a side view of a flexible fastening band according to anembodiment.

FIG. 58 is a perspective view of a flexible fastening band according toan embodiment.

FIG. 59 is a cross-sectional side view of the flexible fastening banddepicted in FIG. 58.

FIG. 60 is a cross-sectional view taken along line XXIII of the flexiblefastening band depicted in FIG. 58.

FIG. 61 is a cross-sectional top view of the flexible fastening banddepicted in FIG. 58 in a first configuration.

FIG. 62 is a cross-sectional top view of the flexible fastening banddepicted in FIG. 58 in a second configuration.

FIG. 63 is an exploded view of a flexible fastening band according to anembodiment.

FIG. 64 is a perspective view of the flexible fastening band depicted inFIG. 63.

FIG. 65 is a cross-sectional view of the flexible fastening banddepicted in FIG. 64.

FIG. 66 is a front perspective view of implant according to anembodiment.

FIG. 67 is a rear perspective view of the implant of FIG. 66.

FIG. 68 is a side view of the implant of FIG. 66.

FIG. 69 is a cross-sectional side view of the implant of FIG. 66.

FIG. 70 is a front perspective view of implant according to anembodiment.

FIG. 71 is a rear perspective view of the implant of FIG. 70.

FIG. 72 is a side view of the implant of FIG. 70.

FIG. 73 is a cross-sectional side view of the implant of FIG. 70.

FIG. 74 is a front perspective view of implant according to anembodiment.

FIG. 75 is a rear perspective view of the implant of FIG. 74.

FIG. 76 is a side view of the implant of FIG. 74.

FIG. 77 is a cross-sectional side view of the implant of FIG. 74.

FIG. 78 is a front perspective view of implant according to anembodiment.

FIG. 79 is a rear perspective view of the implant of FIG. 78.

FIG. 80 is a side view of the implant of FIG. 78.

FIG. 81 is a cross-sectional side view of the implant of FIG. 78.

DETAILED DESCRIPTION

In some embodiments a method comprises disposing an implant into contactwith a first bone portion and into contact with a second bone portion,the implant having (1) a first interface configured to receive arestraining member, and (2) a second interface. The method furthercomprises inserting a portion of the fastener member into the firstinterface. The method further comprises securing the fastener membersuch that the first bone portion and the second bone portion are fixedto each other, at least in part by a substance after the securing, atleast a portion of the substance disposed through the second interface.

In some embodiments an apparatus includes an implant having a face, afirst interface, and a second interface. The face is shaped tosubstantially compliment a shape of a first bone portion, the firstinterface is configured to receive a fastener member, and the secondinterface configured to receive a substance. The implant is configuredto be secured with the fastener member such that the first bone portionand a second bone portion are fused to each other, at least in part bythe substance after the implant is secured by the fastener member. Atleast a portion of the substance disposed through the second interface.

In some embodiments a kit includes a fastener member, a substance, andan implant. The implant can include a first interface configured toreceive a the fastener member, and a second interface configured toreceive a the substance. The implant is configured to be secured withthe fastener member such that a first bone portion and a second boneportion are fused to each other, at least in part by the substance afterbeing secured, at least a portion of the substance disposed through thesecond interface. The fastener member is configured to secure theimplant to the first bone portion and to the second bone portion. Thesubstance configured to fuse the first bone portion to the second boneportion through the second interface.

As used in this specification, the singular forms “a,” “an” and “the”include plural referents unless the context clearly dictates otherwise.Thus, for example, the term “a ratchet” is intended to mean a singleratchet or a combination of ratchets. As used in this specification, asubstance can include any biologic and/or chemical substance, including,but not limited to, medicine, adhesives, etc, and/or a bone graft,including, but not limited to, autograft, allograft, xenograft,alloplastic graft, a synthetic graft, and/or combinations of grafts,medicines, and/or adhesives. While exemplary references are made withrespect to vertebra, in some embodiments another bone can be involved.While specific reference may be made to a specific vertebra and/orsubset and/or grouping of vertebrae, it is understood that any vertebraand/or subset and/or grouping, or combination of vertebrae can be used.

As shown in FIG. 1, the vertebral column 2 comprises a series ofalternating vertebrae 4 and fibrous discs 6 that provide axial supportand movement to the upper portions of the body. The vertebral column 2typically comprises thirty-three vertebrae 4, with seven cervical(C1-C7), twelve thoracic (T1-T12), five lumbar (L1-15), five fusedsacral (S1-S5) and four fused coccygeal vertebrae. FIGS. 2A and 2Bdepict a typical thoracic vertebra. Each vertebra includes an anteriorbody 8 with a posterior arch 10. The posterior arch 10 comprises twopedicles 12 and two laminae 14 that join posteriorly to foam a spinousprocess 16. Projecting from each side of the posterior arch 10 is atransverse 18, superior 20 and inferior articular process 22. The facets24, 26 of the superior 20 and inferior articular processes 22 form facetjoints 28 with the articular processes of the adjacent vertebrae (seeFIGS. 3A and 3B). The facet joints are true synovial joints withcartilaginous surfaces and a joint capsule.

The orientation of the facet joints vary, depending on the level of thevertebral column. In the C1 and C2 vertebrae, for example the facetjoints are parallel to the transverse plane. FIGS. 4A to 6B depictexamples of the orientations of the facet joints at different levels ofthe vertebral column. In the C3 to C7 vertebrae examples shown in FIGS.4A and 4B, the facets are oriented at a 45-degree angle to thetransverse plane 30 and parallel to the frontal plane 32, respectively.This orientation allows the facet joints of the cervical vertebrae toflex, extend, lateral flex and rotate. At a 45-degree angle in thetransverse plane 30, the facet joints of the cervical spine can guide,but do not limit, the movement of the cervical vertebrae. FIGS. 5A and5B depict examples of the thoracic vertebrae, where the facets areoriented at a 60-degree angle to the transverse plane 30 and a 20-degreeangle to the frontal plane 32, respectively. This orientation is capableof providing lateral flexion and rotation, but only limited flexion andextension. FIGS. 6A and 6B illustrate examples of the lumbar region,where the facet joints are oriented at 90-degree angles to thetransverse plane 30 and a 45-degree angle to the frontal plane 32,respectively. The lumbar vertebrae are capable of flexion, extension andlateral flexion, but little, if any, rotation because of the 90-degreeorientation of the facet joints in the transverse plane. The actualrange of motion along the vertebral column can vary considerably witheach individual vertebra.

In addition to guiding movement of the vertebrae, the facet joints alsocontribute to the load-bearing ability of the vertebral column. Onestudy by King et al. Mechanism of Spinal Injury Due to CaudocephaladAcceleration, Orthop. Clin. North Am., 6:19 1975, found facet jointload-bearing as high as 30% in some positions of the vertebral column.The facet joints may also play a role in resisting shear stressesbetween the vertebrae. Over time, these forces acting on the facetjoints can cause degeneration and arthritis.

In some embodiments described herein, a vertebral facet joint implantcan be used to stabilize, fixate, and/or fuse a first vertebra to asecond vertebra to reduce pain, to reduce further degradation of aspine, or of a specific vertebra of a spine, and/or until the firstvertebra and the second vertebra have fused. In some embodiments, thevertebral facet joint implant can be implanted and deployed to restorethe space between facets of a superior articular process of a firstvertebra and an inferior articular process of an adjacent vertebra. Insome embodiments, the vertebral facet joint implant can be implanted anddeployed to help stabilize adjacent vertebrae with adhesives, and/or canbe implanted and deployed to deliver a medication. FIG. 7 depicts ablock diagram of a vertebral facet joint implant (“implant”) 160.Implant 160 includes a first side 162, a second side 164, a fastenerinterface 166, and a substance interface 168. FIGS. 8A-47B depictimplants and fasteners according to different embodiments.

As shown in FIG. 7, implant 160 can be, for example, substantially discshaped. In other embodiments, the spacer can be other shapes, e.g.,square, elliptical, or any other shape. First side 162 and/or secondside 164 can be, for example, convex, concave, or flat. Said anotherway, first side 162 can be concave, convex, or flat, and second side 164can be concave, convex, or flat; for example, first side 162 can beconcave and second side 164 can be concave, first side 162 can beconcave and second side 164 can be convex, etc. In such embodiments, theshape can be determined based on a shape of a bone portion that thefirst side 162 and/or the second side 164 is configured to contact. Saidanother way, the first side 162 and/or the second side 164 can be shapedto substantially compliment the shape of a bone portion. On other words,the first side 162 or the second side 164 need not exactly match theshape of the corresponding bone portion, but instead can have a concaveshape for a bone portion with a generally convex shape where the contactwith the implant is to occur or can have a convex shape for a boneportion with a generally concave shape where the contact with theimplant is to occur. Implant 160 can include any biocompatible material,e.g., stainless steel, titanium, PEEK, nylon, etc.

Implant 160 includes fastener interface 166. Fastener interface 166 canbe configured to retain implant 160 in substantially the same position.Specifically, fastener interface 166 can be configured to accept afastener member (not shown) to substantially prevent movement of implant160. Fastener interface 166 can include an aperture and/or otheropening. Fastener interface 166 can extend through implant 160, e.g. canextend from first side 162 and through to second side 164. In someembodiments, fastener interface 166 can extend through only a portion ofimplant 160, e.g. can extend from first side 162 and through less thanhalf of a width (not shown) of implant 160. Fastener interface 166 canbe disposed on and/or through first side 162, second side 164, and/orboth first side 162 and second side 164. Fastener interface 166 can bedisposed through a center (not shown) of implant 160. In otherembodiments, fastener interface 166 can be disposed anywhere on and/orthrough implant 160, e.g., offset from center. Fastener interface 166can be substantially circular (cylindrical). In other embodiments,fastener interface 166 can be other shapes and/or can be shaped based ona shape of the fastener member, for example, rectangular (cuboid). Insome embodiments. fastener interface 166 can be a irregular shape, basedat least in part in the location of fastener interface 166, see, e.g.FIG. 48, and/or partial shapes, see, e.g. FIG. 23B. Fastener interface166 can include a substantially smooth inner surface (not shown) toallow the fastener member to easily pass through and/or into fastenerinterface 166, and/or can include a threaded inner surface to allow thefastener member to thread into fastener interface 166. While depicted inFIG. 7 as including one fastener interface, implant 160 can include morethan one fastener interface 160.

Implant 160 includes substance interface 168. Substance interface can beconfigured to retain, carry and/or otherwise deliver a substance to aidin fusion, such as, for example, medicines, adhesives, bone graft,and/or combinations of substances. Substance interface 168 can includean aperture and/or other opening. Substance interface 168 can extendthrough implant 160, e.g. can extend from first side 162 and through tosecond side 164. In some embodiments, fastener interface can extendthrough only a portion of implant 160, e.g. can extend from first side162 and through less than half of a width (not shown) of implant 160.Substance interface 168 can be disposed on and/or through first side162, second side 164, and/or both first side 162 and second side 164.Substance interface 168 can be disposed through a center (not shown) ofimplant 160. In other embodiments, substance interface 168 can bedisposed anywhere on and/or through implant 160, e.g., offset fromcenter. Substance interface 168 can be substantially circular(cylindrical). In other embodiments, substance interface 168 can beother shapes and/or can be shaped based on a shape of the fastenermember, for example, rectangular (cuboid). In some embodiments.substance interface 168 can be an irregular shape, based at least inpart in the location of substance interface 168. While depicted in FIG.7 as including one substance interface, implant 160 can include morethan one substance interface 160. The location, size, shape, and/ornumber of substance interface(s) 168 can be determined based on thelocation, size, shape, and/or number of fastener interface(s) 166.

In one embodiment, a device for restoring the spacing between two facetsof a facet joint is provided. As shown in FIGS. 8A and 8B, the devicecomprises a implant 34 with a least two faces, a first face 36 adaptedto contact the articular surface of one facet of the facet joint and asecond face 38 adapted to contact the articular surface of the otherfacet. In one embodiment, the implant 34 has a generally circularprofile and is sized to fit generally within the joint capsule of thefacet joint 28. FIG. 8C illustrates the implant 34 of FIGS. 8A and 8Bpositioned in a facet joint. In other embodiments, the implant can haveany of a variety of profiles, including but not limited to square,rectangle, oval, star, polygon or combination thereof. An octagonalimplant is shown in FIGS. 9A and 9B. In one embodiment, a implant havingthe desired shape is selected from an array of prostheses afterradiographic visualization of the articular processes and/or byradio-contrast injection into the facet joint to visualize the jointcapsule. In one embodiment, the implant has a diameter of about 4 mm toabout 30 mm. In another embodiment, the implant has a diameter of about5 mm to about 25 mm. In still another embodiment, the implant has adiameter of about 10 mm to about 20 mm. In one embodiment, the implanthas a cross-sectional area of about 10 mm² to about 700 mm². In anotherembodiment, the implant has a cross-sectional area of about 25 mm² toabout 500 mm². In still another embodiment, the implant has across-sectional area of about 20 mm² to about 400 mm², or about 25 mm²to about 100 mm².

The implant has a thickness generally equal to about the anatomicspacing between two facets of a facet joint. The implant generally has athickness within the range of about 0.5 mm to about 3.0 mm. In certainembodiments, the implant has a thickness of about 1 mm to about 2 mm. Inone preferred embodiment, the implant has a thickness of about 0.5 mm toabout 1.5 mm. In one embodiment, the thickness of the implant isnonuniform within the same implant. For example, in FIGS. 10A and 10B,the thickness of the implant 42 is increased around the entire outeredge 44, along at least one and, as illustrated, both faces 46, 48. InFIGS. 11A and 11B, only a portion of the edge 44 on one face 46 of theimplant 42 has a thickness that is greater than the thickness of acentral region, and, optionally, also thicker than the typical anatomicspacing between two facets of a facet joint. An increased edge thicknessmay resist lateral displacement of the implant out of the facet joint.

In some embodiments, the implant is configured to provide an improvedfit with the articular process and/or joint capsule. For example, inFIGS. 12A and 12B, the implant 49 has a bend, angle or curve 50 togenerally match the natural shape of an articular facet. FIG. 13 depictsthe implant of FIGS. 12A and 12B positioned in a facet joint. Theimplant may be rigid with a preformed bend. Alternatively, the implantmay be sufficiently malleable that it will conform post implantation tothe unique configuration of the adjacent facet face. Certainembodiments, such as those depicted in FIG. 8C and FIG. 13, the implantis configured to be implanted between the articular processes and/orwithin the joint capsule of the facet joint, without securing of theimplant to any bony structures. Such embodiments can thus be usedwithout invasion or disruption of the vertebral bone and/or structure,thereby maintaining the integrity of the vertebral bone and/orstructure.

In one embodiment, at least a portion of one surface of the implant ishighly polished. A highly polished portion of the implant may reduce thesurface friction and/or wear in that portion of the implant as itcontacts bone, cartilage or another surface of the implant. A highlypolished surface on the implant may also decrease the risk of theimplant wedging between the articular surfaces of the facet joint, whichcan cause pain and locking of the facet joint.

In one embodiment, shown in FIGS. 14A and 14B, at least a portion of onesurface of the implant 50 has a roughened surface 52. A roughenedsurface may be advantageous when in contact with a bone or tissuesurface because it may prevent slippage of the implant 50 against thebone and aid in maintaining the implant 50 in the joint. In oneembodiment, shown in FIGS. 15A and 15B, at least a portion of onesurface of the implant 50 has a porous surface 54. A porous surface 54can be created in any a variety of ways known in the art, such as byapplying sintered beads or spraying plasma onto the implant surface. Aporous surface 54 can allow bone to grow into or attach to the surfaceof the implant 50, thus securing the implant 50 to the bone. In oneembodiment, an adhesive or sealant, such as a cyanoacrylate,polymethylmethacrylate, or other adhesive known in the art, is used tobond one face of the implant to an articular surface.

In one embodiment, one surface of the implant is roughened or porous anda second surface that is highly polished. The first surface contacts orengages one facet of the facet joint and aids in maintaining the implantbetween the articular surfaces. The second surface of the implant ishighly polished and contacts the other facet of the facet joint toprovide movement at that facet joint. FIGS. 16A and 16B represent oneembodiment of the implant comprising a curved or bent disc 56 with aroughened surface 52 on the greater face 58 of the disc and a highlypolished surface 60 on the lesser face 62. FIG. 17 depicts the implantof FIGS. 16A and 16B positioned in a facet joint. The implant generallymaintains a fixed position relative to the facet contacting theroughened surface while the movement of the facet joint is preservedbetween the other facet and the highly polished lesser face of theimplant.

FIGS. 18A and 18B show one embodiment, where the implant 64 comprisestwo separate discs 66, each disc comprising a first face 68 thatarticulates with the complementary first face 68 of the other disc, anda second face 70 adapted to secure the disc to the adjacent bone orcartilage of one facet of the facet joint 28. In one embodiment, thethickness of one disc will generally be about half of the anatomicspacing between two facets of the facet joint. In other embodiments, theimplant comprises three or more discs. In one embodiment the totalthickness of all the discs is generally about 25% to about 300% of theanatomic spacing between the two facets. In another embodiment, thetotal thickness of the discs is generally about 50% to about 150% of theanatomic spacing. In still another embodiment, the total thickness ofthe discs is about 75% to about 125% of the anatomic spacing. Each discof the two-part implant can otherwise also have features similar tothose of a single-disc implant, including but not limited to curved orbent configurations, highly polished or roughened surfaces, and otherfeature mentioned below. The two discs need not have the same size,thickness, configuration or features. FIG. 19 depicts one embodiment ofa two-part implant 64 positioned within a facet joint 28.

The implant can be manufactured from any of a variety of materials knownin the art, including but not limited to a polymer such aspolyetheretherketone (PEEK), polyetherketoneketone (PEKK), polyethylene,fluoropolymer, hydrogel, or elastomer; a ceramic such as zirconia,alumina, or silicon nitride; a metal such as titanium, titanium alloy,cobalt chromium or stainless steel; or any combination of the abovematerials.

In one embodiment, the implant is maintained between the two facets ofthe facet joint by taking advantage of the joint capsule and/or otherbody tissue surrounding the facet joint to limit the migration of theimplant out of the facet joint. In some embodiments, the shape of theimplant itself is capable of resisting displacement of the implant fromits position generally between the facet joint surfaces. In oneembodiment, a concave or biconcave configuration resists displacement ofthe implant by providing an increased thickness at the periphery of theimplant that requires a larger force and/or greater distraction of facetjoint surfaces in order to cause displacement. In other embodiments,surface treatments or texturing are used to maintain the implant againsta facet of the facet joint, as described previously. In someembodiments, a combination of disc configuration, surface texturing andexisting body tissue or structures are used to maintain the position ofthe implant.

Bone growth facilitators, electrical current, or other known techniquesmay be used to accelerate osteoincorporation of textured or microporousanchoring surfaces.

The implant may be configured with a fastener interface to engage(“secure”) a fastener member that facilitates retention of the implantwithin the joint capsule of the facet joint. Use of a fastener membermay be advantageous for preventing migration of the implant over timeuse or with the extreme ranges of vertebral movement that may distractthe articular surfaces sufficiently to allow the implant to slip out.

In one embodiment, shown in FIGS. 20 to 21B, the fastener membercomprises a wire or cable 72 with a portion 74 that engages the implant76 at a fastener interface 78, and at least one other portion 80 thatengages or anchors to the bone or soft tissue surrounding the facetjoint. The wire or cable may be solid, braided or multi-filamented. Thefastener member in this embodiment will be described primarily as acable or wire, but it is to be understood that any of a variety ofelongate structures capable of extending through a central aperture willalso work, including pins, screws, and single strand or multistrandpolymeric strings or weaves, polymeric meshes and fabric and otherstructures that will be apparent to those of skill in the art in view ofthe disclosure herein.

The cross-sectional shape of the fastener member can be any of a varietyof shapes, including but not limited to circles, ovals, squares,rectangles, other polygons or any other shape. The wire or cablegenerally has a diameter of about 0.5 mm to about 2 mm and a length ofabout 5 mm to about 60 mm. In other embodiments, wire or cable has adiameter of about 0.25 mm to about 1 mm, or about 0.75 mm to about 1.25mm. The diameter of the wire or cable may vary along the length of thewire or cable. In one embodiment, the wire or cable has a length ofabout 10 mm to about 40 mm. In another embodiment, the wire or cable hasa length of about 20 mm to about 30 mm.

In one embodiment, shown in FIGS. 21A and 21B, the fastener interface 78of the implant 76 is a conduit between the two faces 82, 84 of theimplant 76, forming an aperture 78. In one embodiment, the aperture 78has a diameter larger than the diameter of the wire or cable 72, toprovide the implant 76 with a range of motion as the facet joint moves.The aperture 78 inside diameter may be at least about 110%, often atleast about 150% and in certain embodiments at least about 200% or 300%or greater of the outside diameter or corresponding dimension of thefastener member in the vicinity of the engagement portion 78. Thecross-sectional shape of the aperture 78 can match or not match thecross sectional shape of the wire or cable used.

In another embodiment, the fastener interface 78 extends only partiallythrough the implant 72. The fastener interface 78 may be locatedgenerally in the center of the implant, or it may be locatedeccentrically, as depicted in FIGS. 22A and 22B. In one embodiment,shown in FIGS. 23A and 23B, the fastener interface 78 is located at theedge 86 of the implant 76 such that the interior surface of the hole 78is contiguous with the outer edge of the implant. This configuration ofthe fastener interface 78 does not require the cable 72 to be threadedthrough the fastener interface 78 and may facilitate engagement of thefastener member with the implant. FIGS. 24A and 24B depict an embodimentcomprising a two-part implant 88. Either a single cable or two separatecables may be used retain both discs within the facet joint. FIGS. 25Aand 25B depict another embodiment comprising a curved implant 90 with afastener interface 78 adapted to accept a cable.

In FIG. 26, the wire or cable 72 is secured to the articular processes20, 22 by tying one or more knots 92 in the cable 72 that can resistpulling of the wire or cable through the articular process. In anotherembodiment, one or both ends of the wire or cable are provided with ananchor to resist migration of the implants. As shown in FIGS. 27A and27B, one or both ends of the wire or cable 72 may be threaded such thata nut 94 can be tightened on the wire or cable 72 to secure the wire orcable to the articular processes 20, 22. FIG. 28 depicts the attachmentof a nut onto a threaded end of a cable. The threaded portion 96 of thewire or cable can be secured to the cable by pressing, crimping ortwisting the threaded 96 portion onto the cable 72. In one embodiment,the threaded portion 96 is made from titanium, titanium alloy, cobaltchromium, stainless steel, or any combination thereof.

In one embodiment, the wire or cable has two threaded ends 96 forengaging the bony or cartilaginous tissue, one portion for each facet ofthe facet joint.

In another embodiment, shown in FIG. 29, the wire or cable is secured tothe articular process with fastener rings 98. As depicted in FIGS. 30Aand 30B, the fastener rings 98 comprise a ring 100 with a central lumen102 and a locking element to facilitate locking the ring 100 to afastener member. The central lumen 102 is adapted to accept insertion ofa wire or cable through it. The illustrated locking element is in theform of a side lumen 104 which is threaded and configured to accept arotatable screw 106 with a proximal end 108, a threaded body 110 and adistal end 112. The threaded body 110 is complementary to the threads ofthe side lumen 104 so that when the screw 106 is rotated at its distalend 112, the proximal end 108 of the screw 106 moves further into thecentral lumen 102 and is capable of applying increasing force to a wireor cable inserted through the central lumen 102. In one embodiment, theforce on the wire or cable is capable of creating a friction fit or amechanical interfit to resist movement between the wire or cable and thefastener ring 98, thereby securing the wire or cable to the articularprocess 20 or 22. As shown in FIGS. 31 to 33, the distal end 112 of thescrew 106 can be configured to engage the wire or cable in any of avariety designs, including but no limited to a blunt tip 114, curved tip116 and piercing tip 118.

In another embodiment, depicted in FIGS. 34A and 34B, the wire or cableis securable to the articular process with a fastener ring 120 haveradially inward biased projections 122 defining a central lumen 124. Thecentral lumen has a cross-sectional shape smaller than that of the wireor cable but is capable of enlargement when the inward projections 122are bent away, as shown in FIGS. 35A and 35B. The inward projections 122apply increasing force to the wire or cable within the central lumen 124as the projections 122 are bent, thereby creating a friction fit.

In one embodiment, one end of the wire or cable fastener member ispreformed with a retainer for engaging the articular process. Theretainer may be a preformed ring, bulb, flared end, T-bar end, or any ofa variety of shapes having a greater cross sectional area than the otherportions of the wire or cable fastener member. This configuration of thewire or cable fastener member is adapted to engage an articular processby passing the free end of a wire or cable fastener member through anarticular process such that the end with the preformed retainer canengage the articular process.

In one embodiment, the wire or cable fastener member is secured to thearticular processes with sufficient laxity or length between the securedends or between the implant and one secured end so that the twoarticular processes are not fixed in position relative to each other andremain capable of performing movements such as flexion, extension,lateral flexion and/or rotation. In one embodiment, the fastener membercomprises a cable of braided polymer, including but not limited to abraided polymer such as PEEK or PEKK, or a braided metal, such asbraided cobalt chromium or titanium. The cable can be selected withdifferent degrees of flexibility to provide different degrees ofmovement at that facet joint. The cable has a first segment capable ofengaging the implant at its fastener interface to limit the movement

In one embodiment, shown in FIG. 36A, the fastener member comprises ascrew or bolt 126 with a proximal end 128, body 130 and distal end 132.The distal end 132 of the screw or bolt is capable of forming amechanical interfit with a complementary fastener interface 134 on theimplant or spacer 136. The distal end 132 typically comprises threads,but other configurations may be used to form a mechanical interfit. Thecomplementary fastener interface 134 on the implant 136 could be athreaded through hole or, a close-ended hole. The proximal end 128 ofthe screw or bolt 126 has a hex or other type of interface known in theart, capable of engaging a rotating tool to manipulate the screw or bolt126. The body of the screw or bolt 126 has a length sufficient to atleast span the length of the hole or conduit created through thearticular process for securing the implant. In FIG. 36B, the fastenermember further comprises a pivotable washer 127 with a pivot surface 129that articulates with the proximal end 128 of the screw 126. In oneembodiment, the pivotable washer 127 is capable of a range of positionsrelative to the screw 126 and provides the screw 126 with a bettersurface area contact with the bone.

FIG. 37 is a cross-sectional view of a facet joint 28 with a spacer 136bolted to one articular process 20 of a facet joint 28. The spacer 136position is fixed relative to one facet 24 of the joint 28, but providesfor spacing and movement of the other facet 26 with respect to thespacer 136. In embodiments comprising a two-part implant, shown in FIGS.38 and 39, each disc may have its own screw or bolt fastener member.FIG. 38 depicts a flat two-part implant 138 and FIG. 39 depicts a curvedtwo-part implant 140.

In some embodiments, shown in FIGS. 40A through 41B, the fastener memberis integral with or attached to the implant and comprises a projection142 from the implant 144 that is adapted to engage the adjacentarticular process or surrounding tissue. In one embodiment, theprojection comprises at least one spike 142 or hook projecting from oneface of the implant 144. In one embodiment, the spike 142 or hook can beribbed, barbed or threaded to resist separation after insertion intobone or tissue. FIG. 42 depicts the implant 144 of FIG. 40A engaged to afacet 24 of the facet joint 28. In one embodiment comprising a two-partimplant 146, shown in FIG. 43, each disc 148 may have its ownprojection-fastener member 142. In some embodiments, as depicted in FIG.44, more than one projection 150 is provided on the implant 152. FIG. 45illustrates the implant of FIG. 44 placed in a facet joint 28. Theprojections 150 may be angled with respect to the implant 152 to resistdislodgement by the movement at the joint.

FIGS. 46A to 47B illustrate embodiments where the fastener membercomprises a projection 154 extending laterally such as from the side ofthe implant 156, and adapted to engage the soft tissue surrounding thefacet joint, rather than a bony or cartilaginous articular process. Inone example, the implant of FIG. 46 could be inserted into a facet jointthrough an incision made in the joint capsule, but the integrity of thejoint capsule opposite the incision site is maintained and used as ananchoring site for the implant. The orientation of the projection can befixed as in FIG. 44, or flexible. FIG. 47 depicts a flexible tether suchas a wire 158 with its proximal end 160 embedded in or otherwiseattached to the implant and one or more barbs which may be attached toits distal end 162. A flexible projection may provide greater selectionof soft tissue anchoring sites for the implant.

In one embodiment, the joint capsule is closed after placement of theimplant. Closure may be performed using adhesives, suturing, stapling orany of a variety of closure mechanisms known in the art.

FIGS. 48A-48C depict an implant 260 according to an embodiment.Specifically, FIG. 48A is a front perspective view of implant 260, FIG.48B is a side view of implant 260, and FIG. 48C is a cross-sectionalside view of implant 260. Implant 260 can be similar to, and havesimilar elements and uses as implant 160 described above. By way ofexample, a fastener interface 266 of implant 260 can be similar tofastener interface 166 of implant 160. Implant 260 includes a concavefirst face 262, a convex second face 264, a centrally disposed circularfastener interface 266, and four irregular shaped substance interfaces268.

FIGS. 49-51 show posterior perspective views of a portion of thevertebral column during a method for fusing adjacent vertebrae using animplant 260 according to an embodiment. As shown in FIG. 49, implant 260and a fastener member 280 can be used to fuse a vertebra V1 and vertebraV2 via the inferior articular process IAP1A of vertebra V1 and thesuperior articular process SAP2A of vertebra V2. Any fastener member caninclude any biocompatible material, e.g., stainless steel, titanium,PEEK, nylon, etc. Also as shown in FIG. 49, an implant 360 and afastener member 380 are used to fuse a vertebra V1 and vertebra V2 viathe inferior articular process IAP of vertebra V1 and the superiorarticular process SAP2B of vertebra V2. In some embodiments, vertebra V1and/or vertebra V2 are fused using only one of implant 260 or implant360. In some such embodiments, one of implant 260 and fastener member280 or implant 360 and fastener member 380 can be used to stabilizevertebra V1 and/or vertebra V2 via one of via the inferior articularprocess IAP1A of vertebra V1 and the superior articular process SAP2A ofvertebra V2, or, via the inferior articular process IAP1B of vertebra V1and the superior articular process SAP2B of vertebra V2. In other suchembodiments, one of fastener member 280 or fastener member 380 can beused to stabilize vertebra V1 and/or vertebra V2 via both of theinferior articular process IAP1A of vertebra V1 and the superiorarticular process SAP2A of vertebra V2 (for example, in combination withimplant 260), and, the inferior articular process IAP of vertebra V1 andthe superior articular process SAP2B of vertebra V2 (for example, incombination with implant 360).

FIG. 52 depicts a flow chart illustrating a method 6000 of using implant260 with fastener member 280 and/or implant 360 with fastener member380. Prior to use of implant 260 and/or implant 360, a patient can beprepared for surgery, at 6002. Some examples of preparations for surgeryare described in U.S. patent application Ser. No. 12/859,009; filed Aug.18, 2010, and titled “Vertebral Facet Joint Drill and Method of Use”(referred to as “the '009 application”), and is incorporated herein byreference in its entirety. In addition to those procedures described inthe '009 application, in some embodiments, the surgical procedure caninclude direct visualization of the vertebra(e) to be stabilized. Saidanother way, the medical practitioner can perform the operation withoutthe use of fluoroscopy. This direct visualization can be possible due tothe small incision necessary for implantation of the implant, forexample, less than about 25 mm, and due to the ease of implanting anddeploying the implant. In some embodiments, the surgical procedure usedcan include forming an opening in body tissue substantially equidistantbetween a first articular process of the first vertebra and a secondarticular process of the first vertebra. A cannula (not shown) can beinserted through the opening and a proximal end of the cannula can bepositioned near the superior articular process SAP2A of vertebra V2. Insome embodiments, the surgical procedure can include preparing the areanear and/or around the vertebra V2 by, for example, removing all or aportion of ligaments, cartilage, and/or other tissue. For example, thearea near and/or around a facet joint can be prepared by removing all ora portion of the facet joint capsule.

A drill or other device can be used to form a lumen in superiorarticular process SAP2A of vertebra V2 and inferior articular processIAP1A of vertebra V1, at 6004. Specifically, the drill can be used toform the lumen in a facet of superior articular process SAP2A ofvertebra V2 and to form the lumen in a facet of inferior articularprocess IAP1A of vertebra V1. Methods and devices for forming lumens invertebra are described in the '009 application. A portion of the surfaceof the facet of SAP2A and IAP1A can be prepared for fusion, at 6006.Specifically, a portion of the surface of the facet can be ground,scored, roughened, sanded, etc, such that the surface of the facet canbetter adhere to any substances to aid in fusion and/or otherwise fusemore readily to the implant. The fastener member 280 can be positionedwithin the cannula and can be advanced through the cannula until aproximal end portion 282 of fastener member 280 is positioned near thelumen of superior articular process SAP2A of vertebra V2. In someembodiments, the proximal end of the cannula can have a bend to directthe proximal end portion 282 of fastener member 280 into the lumen ofsuperior articular process SAP2A of vertebra V2. The proximal endportion 282 of fastener member 280 is inserted into the lumen ofsuperior articular process SAP2A of vertebra V2, at 6008. A substancecan be disposed in a substance interface 268 of implant 260, at 6010. Insome embodiments, implant 260 can have a substance disposed in substanceinterface 268 prior to a surgical procedure, for example, duringmanufacturing of implant 260, post-manufacturing, and/or as part of akit. Implant 260 is inserted between the superior articular processSAP2A of vertebra V2 and inferior articular process IAP1A of vertebraV1, at 6012.

The proximal end portion 282 of fastener member 280 is inserted into thelumen of inferior articular process IAP of vertebra V1, at 6014. Thefastener member can be secured, at 6016. Securing the fastener member280 can be based on the type of fastener member used. By way of example,securing a fastener member similar to a flexible fastener band asdepicted in FIGS. 49-51, can include inserting the proximal end portion282 into a fastening mechanism of a distal end portion 284 of thefastener member 280, and advancing the proximal end portion 282 throughthe fastening mechanism to secure the fastening mechanism. In otherembodiments, fastener member can be secured by tying a first portion thefastener member to a second portion of the fastener member, by screwingthe fastener member into a threaded fastener interface, threading afastener onto a threaded end of a fastener member disposed through afastener interface, combinations of above, etc. In some embodiments,implant 260 can be disposed prior to inserting the proximal end portionof the fastener member 280 into the lumen of superior articular processSAP2A of vertebra V2. The cannula can be removed and/or reinserted atvarious points during the method 6000, including, for example, after theproximal end portion 282 of fastener member 280 is inserted into thelumen formed within the superior articular process SAP2A of vertebra V2,after vertebra V1 and/or Vertebra V2 has been stabilized, or at otherpoints during method 6000.

After the fastener member is secured, superior articular process SAP2Aof vertebra V2 can fuse to inferior articular process IAP of vertebraV1. Fusing can include one or more of bone material from superiorarticular process SAP2A of vertebra V2, bone material from inferiorarticular process IAP1A of vertebra V1, and the substance that fusesarticular process SAP2A of vertebra V2 to inferior articular processIAP1A of vertebra V1 through substance interface 268. In someembodiments, after superior articular process SAP2A of vertebra V2 isfused to inferior articular process IAP1A of vertebra V1, the fastenermember 280 is not removed. In some other embodiments, after superiorarticular process SAP2A of vertebra V2 is fused to inferior articularprocess IAP1A of vertebra V1, all or a portion of the fastener member280 can be removed. In other embodiments, fastener member 280 can beremoved after fusion of superior articular process SAP2A of vertebra V2to inferior articular process IAP of vertebra V1 has started, but hasnot finished.

In addition to the fastener members shown above, such as, for example,fastener member 260, FIGS. 53-65 show fastener members according toother embodiments.

FIG. 53 depicts views of a fastener member 480. Fastener member 480 canbe a flexible fastening band (“band”) 480, FIG. 54 depicts a view of aportion of band 480 can be similar to band 280 described above and caninclude similar components. By way of example, band 480 includes aproximal end portion 482, a first portion 484, a second portion 486, anda distal end portion 488 including a fastening mechanism 490. Incontrast to band 280, band 480 includes a cylindrical second portion 486and each includes a third portion 489. As depicted in FIGS. 53-54, thirdportion 489 is substantially the same shape as first portion 482. Asshown in FIGS. 53 and 54, band 480 includes a gear rack 487 and gears494. Each of gears 494 can be wedge shaped to allow each of gears 494 todisplace the ratchet of fastening mechanism 490 in only one direction.In some embodiments, gears 494 can be other shapes, such as blocks, etc.

FIG. 55 is a side view and FIG. 56 is a top view of a fastener member580. Fastener member 580 can be a flexible fastening hand (“band”) 580according to another embodiment. Band 580 can be similar to band 280 andband 480 described above and can include similar components. By way ofexample, band 580 includes a proximal end portion 582, a first portion584 including a gear rack 587, a second portion 586, and a distal endportion 588 including a fastening mechanism 590 and a ratchet 592. Incontrast to gear rack 487, a cross sectional area of each gear 594 ofgear rack 587 is rectangular in shape instead of wedge shaped.Furthermore, in contrast to first portion 284, first portion 584 iscylindrical in shape instead of cuboidal in shape. In this manner, thelumen 596 of the fastening mechanism 590 is cylindrical in shape. A bandaccording to this embodiment may be particularly useful in deploymentswhere a single band in used to stabilize adjacent vertebrae. In thismanner, the second portion can be disposed within the lumen of the firstarticular process of the first vertebra and a portion of the firstportion can be disposed within the lumen of the second articular processof the first vertebra. In these embodiments the portion of the bandwithin the first articular process of the first vertebra and the portionof the band within in the second articular process of the first vertebracan both have substantially the same shape as the lumen in the firstarticular process of the first vertebra and the lumen in the secondarticular process of the first vertebra. In this manner, and asdescribed above regarding band 480, the amount of open space within thelumens can be minimized, the amount of surface area of the first portionand/or second portion of the band in contact with the lumens canincrease, and subsequently the movement of the first vertebra and/or thesecond vertebra can be reduced or minimized. Furthermore, when movementof the first vertebra and/or the second vertebra does occur, forcesacting against the hand can be more equally distributed throughout thefirst portion and/or the second portion, due at least to the increasedsurface area of the band in contact with the lumens.

FIG. 57 is a side view a fastener member 680. Fastener member 680 can bea flexible fastening band (“band”) 680 according to an embodiment. Band680 can be similar to band 280, band 480, and band 580 described aboveand can include similar components. By way of example, band 680 includesa proximal end portion 682, a first portion 684 including a gear rack687, a second portion 686, and a distal end portion 688 including afastening mechanism 690. Similar to gear rack 587, a cross sectionalarea of each gear 694 of gear rack 687 is rectangular in shape. Incontrast to gear rack 587, each of gears 694 extend the entirecircumference of first portion 684 instead of only a portion of thecircumference of first portion 584. Furthermore, in contrast to firstportion 284, but similar to first portion 584, first portion 684 iscylindrical in shape instead of cuboidal in shape. In this manner, thelumen 696 of the fastening mechanism 690 is cylindrical in shape. A bandaccording to this embodiment may be particularly useful in deploymentswhere the movement and repositioning of the band after implantation maybe difficult. In this manner, because each of the gears can be theentire circumference of the first portion and/or the second portion, thefirst portion and/or the second portion can enter the fasteningmechanism in any radial orientation and still engage the ratchet.

FIGS. 58-62 are views of a fastener member 780. Fastener member 780 canbe a flexible fastening band (“band”) 780 according to anotherembodiment. FIG. 58 is a perspective view and FIG. 59 is across-sectional side view of band 780. FIG. 60 is a cross-sectional viewof band 780 taken along line XXIII. FIG. 61 is a cross-sectional topview of band 780 in a first configuration and FIG. 62 is across-sectional top view of band 780 in a second configuration. Band 780can be similar to band 280 and band 480 described above and can includesimilar components. By way of example, band 780 includes a proximal endportion (not shown), a first portion 784 including a gear rack 787 (seeFIG. 59), a second portion 786, and a distal end portion 788 including afastening mechanism 790 and a ratchet 792. In contrast to band 280 andband 480, band 780 includes a reinforcement piece 772.

Reinforcement piece 772 can include any of the materials described abovefor a fastener member. In some embodiments, reinforcement piece 772 caninclude a material stronger than second portion 786 and/or first portion784, for example, first portion 784 and second portion 786 can includePEEK and reinforcement piece 772 can include titanium. As shown in FIG.59, reinforcement piece 772 can be disposed within band 780approximately along the entire length of second portion 786, and aportion of reinforcement piece 772 can be disposed within the distal endportion 788. In some embodiments, reinforcement piece can include alength along at least a portion of the length of second portion 786and/or first portion 784 but not the distal end portion. In someembodiments, reinforcement piece 772 can be disposed only within secondportion 786. Reinforcement piece 772 can have a length in firstdimension (length), a length in a second dimension (width), and a lengthin a third dimension (height). As described herein, a reinforcementpiece be different shapes that can include more or fewer dimensions.

The reinforcement piece can be molded within the band. Said another way,in embodiments where the first portion, the second portion, and or thedistal end portion are moldable materials, the reinforcement piece canbe placed in the mold and the moldable materials can be injected orotherwise put in the mold around the reinforcement piece. In otherembodiments, each portion of the band (for example, the proximal endportion, the first portion, the second portion, the third portion,and/or the distal end portion) around the reinforcement piece can have atop half and a bottom half, and each of the top half and the bottom halfcan be placed around the reinforcement piece, and sealed. As shown inFIG. 61, reinforcement piece 772 includes support members 774. WhileFIG. 61 shows reinforcement piece 772 including four support members774, in some embodiments, more or fewer support members 774 can be used.Support members 774 can maintain the position of reinforcement piece 772during the molding and/or assembly process of band 780. As shown in FIG.62, support members 774 are removed before band 780 is used.

As shown in FIG. 60, reinforcement piece 772 can has a substantiallyuniform cuboidal shape. In other embodiments, reinforcement piece 772can have other shapes. The shape of the reinforcement piece can beselected depending on the desired bending and/or torsion characteristicsof the material chosen. By way of example, a substantially planarcuboidal shape can provide a greater increase in bending strength whileproviding a lesser increase in torsion strength, a cylindrical shape canprovide an increase in bending strength while providing very littleincrease in torsion strength, a substantially square and/or tubularcuboidal shape can provide similar bending and torsion increases. Anyshape can be selected to achieve the desired bending and torsionstrength. Combinations of materials and shapes can also be considered.For example, a material having higher torsion strength may be combinedwith a shape having a lower torsion strength to combine for the desiredtorsion strength. As shown in FIGS. 61 and 62, reinforcement piece 772includes holes 776 distributed along the length of the first dimension.While FIGS. 61 and 62 shows band 780 including many holes 776, in someembodiments, more or fewer holes 776 can be used. FIGS. 61 and 62 depictholes 776 distributed substantially equally along the length of thefirst dimension, in some embodiments, the holes can be distributeddifferently or along different dimensions depending on the shape and/ormaterial chosen, and/or whether the reinforcement piece is solid orhollow. Holes 776 can be configured to reduce the weight ofreinforcement piece 772 while still provided band 780 additionalstrength. Holes 776 can be round, oval, square, or any other shape.

FIG. 63 is an exploded view, FIG. 64 is a perspective view, and FIG. 65is a cross-sectional view of a fastener member 880. Fastener member 880can be a flexible fastening band (“band”) 880 according to anotherembodiment. Band 880 can be similar to band 280 and band 480 describedabove and can include similar components. By way of example, band 880includes a proximal end portion 882, a first portion 884, a secondportion 886 including a gear rack 887, a distal end portion 888, afastening mechanism 890 and a ratchet 892. In contrast to band 280 andband 480, the fastening mechanism 890 of band 880 is separately formedfrom distal portion 888 of band 880. While second portion 886 of band880 is shown in FIGS. 63-65 as having a substantially cuboidal shape, insome embodiments, second portion 886 can be substantially cylindrical inshape or any other appropriate shape discussed herein. As shown in FIGS.64 and 65, band 880 includes a gear rack 887 and gears 894. Each ofgears 894 can be wedge shaped to allow each of gears 894 to displace aratchet 892 of fastening mechanism 890 in only one direction. In someembodiments, gears 894 can be other shapes, such as blocks, or any otherappropriate shape discussed herein. As shown in FIGS. 63-65, distal endportion 888 can be substantially circular in shape and can have adiameter greater than a width of second portion 886. In otherembodiments, distal portion 888 can have other shapes, for example,oval, rectangular, square, etc.

In addition to the implants shown above, such as, for example, implant160, FIGS. 66-81 show implants according to other embodiments.

FIGS. 66-69 depict an implant 1060 according to an embodiment.Specifically, FIG. 66 is a front perspective view of implant 1060, FIG.67 is a rear perspective view of implant 1060, FIG. 68 is a side view ofimplant 1060, and FIG. 69 is a cross-sectional side view of implant1060. Implant 1060 can be similar to, and have similar elements and usesas implant 160 and implant 260 described above. By way of example, afastener interface 1066 of implant 1060 can be similar to fastenerinterface 166 of implant 160, and similar to fastener interface 266 ofimplant 260. Implant 1060 includes a concave first face 1062, a convexsecond face 1064, a centrally-disposed substantially-circular fastenerinterface 1066, and six substantially-circular shaped substanceinterfaces 1068.

FIGS. 70-73 depict an implant 1160 according to an embodiment.Specifically, FIG. 70 is a front perspective view of implant 1160, FIG.71 is a rear perspective view of implant 1160, FIG. 72 is a side view ofimplant 1160, and FIG. 73 is a cross-sectional side view of implant1160. Implant 1160 can be similar to, and have similar elements and usesas implant 160 and implant 260 described above. By way of example, afastener interface 1166 of implant 1160 can be similar to fastenerinterface 166 of implant 160, and similar to fastener interface 266 ofimplant 260. Implant 1160 includes a concave first face 1162, a convexsecond face 1164, a centrally-disposed substantially-circular fastenerinterface 1166, and five rounded rectangular shaped substance interfaces1168.

FIGS. 74-77 depict an implant 1260 according to an embodiment.Specifically, FIG. 74 is a front perspective view of implant 1260, FIG.75 is a rear perspective view of implant 1260, FIG. 76 is a side view ofimplant 1260, and FIG. 77 is a cross-sectional side view of implant1260. Implant 1260 can be similar to, and have similar elements and usesas implant 160 and implant 260 described above. By way of example, afastener interface 1266 of implant 1260 can be similar to fastenerinterface 166 of implant 160, and similar to fastener interface 266 ofimplant 260. Implant 1260 includes a concave first face 1262, a convexsecond face 1264, a centrally-disposed substantially-circular fastenerinterface 1266, and several substantially-circular shaped andvariably-sized substance interfaces 1268.

FIGS. 78-81 depict an implant 1360 according to an embodiment.Specifically, FIG. 78 is a front perspective view of implant 1360, FIG.79 is a rear perspective view of implant 1360, FIG. 80 is a side view ofimplant 1360, and FIG. 81 is a cross-sectional side view of implant1360. Implant 1360 can be similar to, and have similar elements and usesas implant 160 and implant 260 described above. By way of example, afastener interface 1366 of implant 1360 can be similar to fastenerinterface 166 of implant 160, and similar to fastener interface 266 ofimplant 260. Implant 1360 includes a concave first face 1362, a convexsecond face 1364, a centrally-disposed substantially-circular fastenerinterface 1166, four irregular shaped substance interfaces 1368, andfour projections 1369. Each of the four projections 1369 can engage, orother wise dig, latch, lock, or hook into or onto, a bone portion toprevent or reduce movement of the implant 1360, such as, for example,rotation of implant 1360, longitudinal movement of implant 1360, and/orlateral movement of implant 1360. In this manner, the projections 1369can secure implant 1360 to a bone portion during a fusion procedure. Insome embodiments, projections 1369 can substantially maintain a positionof implant 1369 after a fastener member is removed.

While various embodiments have been described above, it should beunderstood that they have been presented by way of example only, notlimitation, and various changes in form and details may be made. Forexample, while the descriptions given are with reference to stabilizingvertebra, another bone(s), such as, for example, a sternum and/or arib(s) could be stabilized using the fastener members and implantsdescribed herein. In another example, a fastener member can be used tostabilize and/or fixate an intramedullary (IM) rod or nail. For example,the fastener member can be used at different longitudinal locationsalong an IM rod or nail, and used to couple adjacent bone portions tothe IM rod or nail. In such situations, a given fastener member can fixa first bone portion, the IM rod or nail, and a second bone portion, allof which are positioned between the distal portion and the proximalportion of the fastener member. In yet another example, a fastenermember can be used to stabilize and/or fixate a bone fragment. Whilevarious embodiments have been described above with regard to naturalbone spaces, (e.g., the space between an inferior articulate process anda superior articulate process), in other embodiments, the bone spacingcan be man-made (e.g., sternum split during a heart procedure), and/ordue to an injury (e.g., broken bone).

Where methods described above indicate certain events occurring incertain order, the ordering of certain events can be modified.Additionally, certain of the events can be performed concurrently in aparallel process when possible, as well as performed sequentially asdescribed above. Any portion of the apparatus and/or methods describedherein may be combined in any combination, except mutually exclusivecombinations. The embodiments described herein can include variouscombinations and/or sub-combinations of the functions, components and/orfeatures of the different embodiments described. For example, FIGS. 54and 56 depict band 580 including a single ratchet 592, and FIG. 57depicts band 680 including a single ratchet 692, however, in someembodiments, any of the fastener members can include any number ofratchets. Similarly, any of fastener members can include a reinforcementpiece and/or a implant. Furthermore, while one embodiment of an implantmay be shown in use with one embodiment of a fastener member, in otherembodiments, implants and fastener member can be used with otherimplants and fastener members. For example, while FIG. 28 depicts animplant being secured with a threaded wire, in some embodiments, aflexible fastening band can be used.

What is claimed is:
 1. An apparatus, comprising: an implant having aface, a second face, an interface, and a second interface, the faceshaped to substantially compliment a shape of a first bone portion, theinterface configured to receive a fastener member, wherein the interfacedefines a first aperture, wherein the second interface defines at leasttwo second apertures extending from the face to the second face, each ofthe second apertures having a different shape or size than the firstaperture, the implant configured to be secured with the fastener membersuch that the first bone portion and a second bone portion are fused toeach other after the implant is secured by the fastener member.
 2. Theapparatus of claim 1, wherein the second face is shaped to substantiallycompliment a shape of the second bone portion.
 3. The apparatus of claim1, wherein the second interface is configured to receive a bone graft,the first bone portion and a second bone portion are fused to each othervia the bone graft.
 4. The apparatus of claim 1, wherein a surface ofthe face is roughened or porous.
 5. The apparatus of claim 1, whereinthe interface is disposed substantially in a center of the face.
 6. Theapparatus of claim 1, wherein each of the second apertures of the secondinterface has an irregular shape.
 7. The apparatus of claim 1, whereineach of the second apertures of the second interface is disposedsubstantially equidistant about a center of the face.
 8. The apparatusof claim 1, wherein each of the second apertures is enclosed.
 9. Theapparatus of claim 1, wherein the face of the implant is concave, thesecond face of the implant is convex.
 10. The apparatus of claim 1,wherein the at least two second apertures encircle the first aperture.11. A kit, comprising: a fastener member; and an implant having aninterface configured to receive the fastener member, wherein theinterface defines a first aperture; the implant having a secondinterface, wherein the second interface defines a plurality of aperturesextending entirely through the implant, each of the plurality ofapertures having a different shape or size than the first aperture; thefastener member configured to secure the implant to the first boneportion and to the second bone portion such that a first bone portionand a second bone portion are fused to each other after being secured.12. The kit of claim 11, wherein the interface is disposed substantiallyin a center of a face of the implant.
 13. The kit of claim 11, whereineach of the plurality of apertures of the second interface has anirregular shape.
 14. The kit of claim 11, wherein the second interfaceis configured to receive a bone graft, the first bone portion and asecond bone portion are fused to each other via the bone graft.
 15. Thekit of claim 11, wherein the fastener member is a flexible fasteningband.
 16. The kit of claim 11, wherein the implant includes a face, theface is roughened or porous.
 17. The kit of claim 11, the implantfurther including a face shaped to substantially compliment a shape ofthe first bone portion.
 18. The kit of claim 11, wherein each of theplurality of apertures of the second interface is enclosed.
 19. The kitof claim 11, wherein each of the plurality of apertures of the secondinterface is disposed substantially equidistant about a center of a faceof the implant.
 20. The kit of claim 11, wherein plurality of aperturesencircle the first aperture.